[libata] Improve timeout handling
On a timeout call a device specific handler early in the recovery so that
we can complete and process successful commands which timed out due to IRQ
loss or the like rather more elegantly.
[Revised to exclude the timeout handling on a few devices that inherit from
SFF but are not SFF enough to use the default timeout handler]
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
diff --git a/drivers/ata/libata-eh.c b/drivers/ata/libata-eh.c
index ea89091..0183131 100644
--- a/drivers/ata/libata-eh.c
+++ b/drivers/ata/libata-eh.c
@@ -547,7 +547,7 @@
/* For new EH, all qcs are finished in one of three ways -
* normal completion, error completion, and SCSI timeout.
- * Both cmpletions can race against SCSI timeout. When normal
+ * Both completions can race against SCSI timeout. When normal
* completion wins, the qc never reaches EH. When error
* completion wins, the qc has ATA_QCFLAG_FAILED set.
*
@@ -562,7 +562,19 @@
int nr_timedout = 0;
spin_lock_irqsave(ap->lock, flags);
+
+ /* This must occur under the ap->lock as we don't want
+ a polled recovery to race the real interrupt handler
+
+ The lost_interrupt handler checks for any completed but
+ non-notified command and completes much like an IRQ handler.
+
+ We then fall into the error recovery code which will treat
+ this as if normal completion won the race */
+ if (ap->ops->lost_interrupt)
+ ap->ops->lost_interrupt(ap);
+
list_for_each_entry_safe(scmd, tmp, &host->eh_cmd_q, eh_entry) {
struct ata_queued_cmd *qc;
@@ -606,6 +618,9 @@
ap->eh_tries = ATA_EH_MAX_TRIES;
} else
spin_unlock_wait(ap->lock);
+
+ /* If we timed raced normal completion and there is nothing to
+ recover nr_timedout == 0 why exactly are we doing error recovery ? */
repeat:
/* invoke error handler */